W Künzi

University of Zurich, Zürich, Zurich, Switzerland

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Publications (40)49.27 Total impact

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    ABSTRACT: Purpose Although the literature is encouraging with regard to the survival rate of arterialized free venous flaps, previously reported difficulty in healing owing to early venous congestion and subsequent epidermolysis continues to prevent their widespread application. We report 14 arterialized free venous flaps for primary reconstruction of the hand, with inflow in the arterialized vein running against the valves. Methods Between February 2010 and May 2012, we performed 14 arterialized free venous flaps, each of which included at least 2 veins running in parallel. The arterialized vein was anastomosed in a retrograde manner, with the inflow running against the valves. All flaps were customized with regard to dimension, shape, quality of skin, pedicle length, vessel size, inclusion of additional anatomical structures, and donor site. The flaps were used to cover small, medium, and large defects; 2 flaps were larger than 100 cm2. Three flaps were injected with indocyanine green on the table after harvesting, to visualize the vascular tree of the flap. These 3 flaps were then monitored with systemic indocyanine green injection and an infrared camera for 3 days postoperatively. Results All but 1 flap survived. Venous congestion and epidermolysis were observed in 2 small flaps. The flaps injected with indocyanine green displayed a ramified vascular tree with no arteriovenous flow-through phenomenon. Conclusions Arterialized free venous flaps with retrograde arterial flow offer thin and pliable coverage that fits easily around the contours of the hand. They are easy to harvest, with little donor site morbidity. Tendons or nerves can be incorporated for reconstruction of composite defects. Clinical relevance Our series suggests the possibility of routine use of a free venous flap with retrograde arterial flow for reconstruction of the hand. Type of study/level of evidence Therapeutic IV.
    The Journal of hand surgery 01/2014; 39(3):511–523. · 1.33 Impact Factor
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    ABSTRACT: Breast augmentation with implants is the most commonly performed aesthetic surgical procedure. However, the risk of complications requiring revision surgery with unsatisfactory final results is often underestimated. In a 10-year retrospective study, patients receiving implant exchange or implant removal after breast augmentation were reviewed with regards to surgical technique, implant type and position, complications and follow-up interventions. As many as 230 patients were included with a mean age of 40.23 years. A total of 192 (83.5%) had primary augmentation for aesthetic reasons, 24 (10.4%) patients were transsexuals and 14 (6.1%) were treated for malformations. The median primary implant size was 260, 224 and 327 g for aesthetic, malformation and transsexual patients, respectively. Capsular contracture was the leading cause for revision in aesthetic patients whereas size and shape were the main reasons for reoperation in transsexual and malformation patients, respectively. As many as 25% of patients required more than one revision procedure. The time between operations in aesthetic augmentation patients was significantly shorter for the second revision procedure (106.2 months vs. 11.4 months, p < 0.0001). The cumulative risk for needing a second revision procedure in aesthetic patients at 12 months was 24.5%. There was no correlation between implant site, size, position or type of complication and the number of revision procedures. Our data highlight the high complication rate of revision surgery involving implant removal or replacement. We conclude that patients must be routinely informed of the high risk and arduous consequences of revision surgery, which should be stated as such in the written consent for the procedure.
    Journal of Plastic Reconstructive & Aesthetic Surgery 10/2012; · 1.44 Impact Factor
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    ABSTRACT: Up to 9% of all burn victims in western countries are reported to have been caused by self-immolation with suicidal intent and usually involve extensive injuries. The authors sought to identify differences between suicide burn victims as opposed to those who sustained their injuries accidentally with regard to injury severity and mortality and determine the possible impact of suicide as a prognostic variable in the context of a scoring system such as the Abbreviated Burns Severity Index (ABSI). The data of all burns patients treated at the Specialist Burns Intensive Care Unit, University Hospital Zürich, between 1968 and 2008 were analyzed retrospectively. Of the 2813 patients included in the study, 191 were identified as attempted suicides, most commonly involving the use of accelerants. Thirty percent of all suicide victims had preexisting psychiatric diagnoses. Suicide victims presented with significantly more extensive burns (53.7%, ±0.98 SEM vs 21.4 %, ±0.36 SEM, P < .0001), had higher total ABSI scores (8.4, ±0.23 SEM vs 6.6, ±0.05 SEM, P < .0001), and had higher mortality rates (42.9% [83/191] vs 16.3% [426/2622]) than accident victims. Furthermore, logistic regression revealed suicide to be a significant predictor of mortality as inhalation injury (odds ratio 2.2, 95% confidence interval 1.4-3.5, P < .0003 and odds ratio 2.4, 95% confidence interval 1.4-4.0, P < .0009, respectively). The odds of dying from an attempted suicide are twice as high compared with those of accident patients in the same ABSI category, making suicide a powerful predictor of mortality. The authors therefore suggest including it as a fixed variable in scoring systems for estimating a patient's mortality after burn injuries such as the widely used ABSI.
    Journal of burn care & research: official publication of the American Burn Association 01/2012; 33(5):642-8. · 1.54 Impact Factor
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    ABSTRACT: In light of changes in patient demographics together with constant developments in burn care, the predictive accuracy of the Abbreviated Burns Severity Index (ABSI) - first described in 1982 - for estimating the mortality of present day burns patients, may be questionable. We reviewed the records of 2813 burns patients treated between January 1968 and December 2008 in the intensive care unit at our institution, aiming to identify emerging discrepancies between the estimated and calculated outcome, based on each of the ABSI variables and the total burn score. The predictive value of each of the defined ABSI variables was confirmed to be highly significant. Univariable and multivariable analysis revealed an exponential increase in odds ratio (OR) for mortality for patients older than 60 years and more than 30% TBSA burned and showed OR values over 10 times higher than other significant variables like inhalation injury. Nevertheless, the ABSI for the estimation of mortality in our entire patient collective was highly accurate and could not be optimised by adapting the point distribution to the increase in OR. Our data indicates that despite significant changes in patient demographics and medical advances over the past 30 years, the ABSI scoring system is still an accurate and valuable tool in the prediction of burn patient mortality.
    Burns: journal of the International Society for Burn Injuries 04/2011; 37(6):958-63. · 1.95 Impact Factor
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    ABSTRACT: This study aims to review our experience in the surgical management of microstomia following facial burns. For this retrospective study, we searched our burn patients' database for oral commissuroplasties with local mucosal flaps and reviewed the 18 patients suffering from microstomia after facial burns who had been operatively treated between 1995 and March 2007. Fifteen of the patients were primarily treated for severe facial burns in our burns unit, three were referred to our outpatients clinic for secondary reconstruction. Reconstruction of the oral commissures was performed according to one of the following methods: (1) triangular scar excision and mucosal Y-V advancement (n=10), (2) scar excision and wound closure with full-thickness or split-skin graft (n=4) and (3) division of the contracture and closure of the resulting defect with two rhomboid mucosal flaps per side (n=4). All patients showed acceptable aesthetic results and a good functional outcome. Apart from minor wound-healing disturbances, which neither required surgery nor worsened the result, no complications were observed. Patient satisfaction was high. Commissuroplasty is an early functional post-burn corrective procedure that often must be performed prior to completion of scar maturation. Mucosal advancement flaps are a viable procedure for the treatment of microstomia after facial burns, resulting in good aesthetic and functional outcome. Direct scar excision and skin grafting, although unavoidable in cases of extensive perioral scarring, frequently produces inferior results.
    Journal of Plastic Reconstructive & Aesthetic Surgery 11/2009; 63(4):e351-7. · 1.44 Impact Factor
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    ABSTRACT: The aim of this study was to provide an increased level of evidence on surgical management of high-tension electrical injuries compared with thermal burns using a case-controlled study design. Sixty-eight patients (64 males, 4 females, aged 33.7 +/- 13 years) with high-tension electrical burns were matched for age, gender, and burnt extent with a cohort of patients sustaining thermal burns. Data were analyzed for cause of accident (occupational vs nonoccupational), concomitant injuries, extent of burn and burn depth, surgical management, complications, and hospital stay. High-tension electrical burn patients required an average of 5.2 +/- 4 operations (range, 1-23 operations) compared with 3.3 +/- 1.9 (range, 1-10 operations) after thermal burns (P = .0019). Amputation rates (19.7% vs 1.5%), escharotomy/fasciotomy rates (47% vs 21%), and total hospitalization days (44 d vs 32 d) were significantly higher in high-tension electrical injuries (P < .05). Creatinine kinase levels were significantly elevated during the first 2 days in patients with subsequent amputations. Free flap failure was observed during the first 4 weeks after the trauma, whereas no flap failure occurred at later stages. Local, pedicled, and distant flaps were used in 15% of the patients. The mortality in both groups was 13.2% vs 11%, respectively (nonsignificant). High-voltage electrical injury remains a complex surgical challenge. When performing free flap coverage, caution must be taken for a vulnerable phase lasting up to 4 weeks after the trauma. This phase is likely the result of a progressive intima lesion, potentially hazardous to microvascular reconstruction. The use of pedicle flaps may resemble an alternative to free flaps during this period.
    Journal of burn care & research: official publication of the American Burn Association 04/2009; 30(3):400-7. · 1.54 Impact Factor
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    ABSTRACT: The transverse rectus abdominis muscle flap is widely used in free microvascular tissue transfer for breast reconstruction following mastectomy. Flap survival may be compromised by failure at the microsurgical anastomosis due to both venous and arterial thrombosis. It is unclear, whether hereditary thrombophilia represents a risk factor for early thrombotic occlusion following free flap procedures. We present a case of a patient with previously diagnosed activated protein C resistance caused by heterozygous factor V (position 1691 G-->A) Leiden mutation in whom a free transverse rectus abdominis muscle flap was performed. The postoperative course was complicated by repeated thrombosis of both the venous and arterial part of the anastomosis. Immediate thrombectomy and repeated arteriography allowed for partial flap salvage. More data are needed to analyze the impact of hereditary thrombophilia on microvascular anastomosis failure.
    Clinical and Applied Thrombosis/Hemostasis 12/2008; 16(2):199-203. · 1.02 Impact Factor
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    ABSTRACT: Burn injuries are a serious threat to individuals with altered consciousness during epilepsy. The objective of this study detailing 33 individuals who sustained scalds or burn injuries during an epileptic seizure, was to clarify typical injury mechanisms, extent, therapy and sequelae of these injuries and thus identify potential preventive measures to protect this special population from thermal trauma. Overall, 16 women and 17 men with a mean age of 39.6 (range: 21 - 76) years were included in this retrospective review. The burned body area averaged 16 % (maximum: 51 %), 30 of the 33 patients (91 %) required burn wound excision and skin grafting. The mean ABSI score was 5.5 (range: 3 to 11) points. Thermal trauma mostly occurred as hot water scalds (n = 19) during showering or bathing in a tub (n = 15), followed by falls during cooking or into open fire. None of our patients was informed about the risk of experiencing severe thermal injuries during epileptic seizures. The length of intensive care averaged 33 days (maximum: 79 days), all patients survived. The estimated treatment costs were at least 50,000 Euros per patient. In conclusion, epileptic seizures can cause severe and deep thermal trauma. Our data shows that most of these injuries happen at home and may be easily prevented by simple safety devices, such as water thermo-regulators or the avoidance of high-risk situations, it seems advisable to inform patients with epilepsy and their families and care-givers of this specific danger.
    Handchirurgie · Mikrochirurgie · Plastische Chirurgie 12/2008; 40(6):372-6. · 0.86 Impact Factor
  • The Journal of trauma 10/2008; 65(3):722-31; discussion 731. · 2.35 Impact Factor
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    ABSTRACT: To assess the nature and rates of complications and recurrences after completion lymph node dissection (CLND) following positive sentinel lymph node biopsy (SLNB) in melanoma patients. In contrast to SLNB, CLND is associated with considerable morbidity. CLND delays nodal recurrence, thereby prolonging disease-free survival (DFS), but not overall melanoma-specific survival. Elaborate studies on morbidity and recurrence rates after CLND are scarce. Therefore, many controversies concerning extent and nature of CLND exist. We conducted a retrospective study on 100 melanoma patients, on whom we performed CLND between October 1999 and December 2005. The median observation period was 38.8 months. We performed a total of 102 CLNDs, [46.1% axillary (47/102), 42.2% groin (43/102), 11.8% neck (12/102)]. Groin dissection (GD) and axillary dissection (AD) led to comparable morbidity (47.6% and 46.8%), but complications were more severe in GD, mandating additional surgery in 25.6% (11/43), versus 8.5% (4/47) in AD. Of the GD patients, 18.5% (8/43) were readmitted for complications compared with 10.4% (5/47) of AD patients. Only 8.3% (1/12) of ND patients suffered complications, mandating neither readmittance nor further surgery. During the median observation period, 65 (65%) of these patients showed DFS, and 35 (35%) exhibited recurrences after a median DFS of 12.5 months. Of the recurrences, 31.4% were nodal, 42.9% distant, and 25.7% local/in-transit. Of our AD patients, 28.3% suffered recurrences (13/46), as did 33.3% of the GD (14/42) and 66.7% of the ND patients (8/12). CLND is fraught with considerable morbidity. Local control of the dissected nodal basins was achieved with a modified radical approach in ADs (levels I + II only) and, to a lesser extent, GDs, but not in NDs. Clinical trials are necessary to establish guidelines on the extent of lymphatic dissection.
    Annals of Surgery 05/2008; 247(4):687-93. · 6.33 Impact Factor
  • Handchirurgie Mikrochirurgie Plastische Chirurgie - HANDCHIR MIKROCHIR PLAST CHIR. 01/2008; 40(06):372-376.
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    ABSTRACT: High-voltage burns represent a challenging surgical entity. Compared to conventional burns, these injuries are characterized by an increased morbidity and worse potential for rehabilitation. The aim of the present study was to analyse the management of high-voltage injuries during the early posttraumatic period with special emphasis on the surgical procedures. PATIENTS/MATERIAL AND METHOD: We retrospectively evaluated the medical records of patients with electrical injuries treated from 1995 - 2007. A total of 61 patients (57 men, 4 females, mean age: 34 +/- 13 years) with high-voltage burns was included for analysis. The majority of high-voltage burns was work-related (75 %). The mean total burn area was 35 % of the total body surface, with a mean of 29 % deep burns. An average of 4.8 +/- 4 operations were performed per patient (range: 1 - 23 operations). Surgical procedures included repeated debridement/necrectomy (100 % of all patients), early escharotomy/fasciotomy (47.5 %), and amputations (18 %). 14 patients (23 %) underwent reconstructive surgery using either local or free flaps. The mortality rate was 15 %. The surgical management of high-voltage burns is characterised by repetitive debridements and necrectomies. Despite an aggressive approach to remove necrotic tissue, the mortality in this type of injury is considerably high. Limb salvage may be achieved with the use of free microvascular flaps. However, an amputation of necrotic extremities must be considered in the copresence of septic complications.
    Handchirurgie · Mikrochirurgie · Plastische Chirurgie 11/2007; 39(5):345-9. · 0.86 Impact Factor
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    ABSTRACT: Early complete wound closure and thus reduction of excessive scar formation still represent a major clinical challenge in severely burned patients. A novel concept to cover large burn wounds consists of the application of non-cultured epithelial cell suspension within the first days. Herein, we report our experiences with three patients treated with CellSpray XP. According to the amount of cell suspension required, a skin biopsy was harvested and then processed in an external laboratory. Two days later the suspension containing autologous non-cultured keratinocytes was applied using an aerosol system. All wounds healed rapidly and virtually no signs of hypertrophic scarring were observed 6 months later.
    Journal of Plastic Reconstructive & Aesthetic Surgery 10/2007; 61(11):e1-4. · 1.44 Impact Factor
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    ABSTRACT: The objective of this investigation was to evaluate the indications for and the functional and cosmetic results of mandible reconstruction using free vascularized fibular flaps. It was also designed to assess the patients’ quality of life, daily activities, and self-esteem, with special emphasis on patient satisfaction. We conducted a retrospective chart review of all patients who underwent osseus or osteocutaneous free flap reconstruction of the mandible over a 10-year period (1992–2002). Those in whom a vascularized fibular flap was used were included in the study and invited for a follow-up comprehensive physical examination and x-ray evaluation. A questionnaire was also administered to evaluate patient satisfaction. Twenty-six patients were included in the study. Fourteen patients died after an average of 2 years and 9 months postoperatively due to their prognosis despite surgical intervention and adjuvant therapy. Of the remaining 12 patients, 6 appeared for the follow-up evaluation, 2 were unavailable for follow-up, and 4 denied participating. Of these 6 patients, all experienced a decrease in pain and were satisfied with their results. At the time of the latest follow-up, they experienced some difficulties swallowing, and in 3 patients, their articulation was impaired. All 6 patients would undergo the procedure again. Reconstruction of the mandible using a vascularized fibular graft produces satisfactory functional and cosmetic results. In benign lesions, the procedure is highly indicated. However, in the case of malignancy, most patients do not survive their primary tumor. Given the patients limited life expectancy, the improvement in their quality of life as a result of the improved appearance and function of the reconstructed mandible needs to be weighed against the potential morbidity of the operative intervention on an individual basis.
    European Journal of Plastic Surgery 02/2007; 29(6-29):293.
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    ABSTRACT: The surgical therapy of oropharyngeal carcinoma by means of a free jejunum graft is an established procedure. The application of a monitor segment for postoperative flow control turned out to be a reasonable modification. In this study, we examine the results over a period of 16 years retrospectively. Between 1988 and 2004, 53 patients underwent oropharyngeal reconstructions by means of 58 free jejunum grafts at the clinic for reconstructive surgery in cooperation with the clinic for otorhinolaryngology. All patients were examined postoperatively with the help of a small jejunum loop in the function of a monitor segment to survey flap vitality. Between the 7th and 11th postoperative day the patients were administered Gastrografin to evaluate oesophagojejunal anastomoses. The survival ratio of the transplants in this series amounted to 90.6 %. All anastomoses were initially passable and leak-proof. After a complete loss of the first graft, five patients were successfully reconstructed with a second jejunum graft. In one patient, the vessel anastomoses had to be revised. In two patients, newly formed stenoses were postoperatively treated with a bougie during hospitalisation. In four patients, fistula formation was detected in the follow-up examination. Substantial advantages of the free jejunum graft compared to other alternative free or local tissue transfers are the excellent functional results, the simple local tumour monitoring and the low complication rate.
    Handchirurgie · Mikrochirurgie · Plastische Chirurgie 01/2007; 38(6):398-402. · 0.86 Impact Factor
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    ABSTRACT: Summary:Assessing the vascular status and anatomy of the lower extremity is of crucial importance when planning the coverage of a tissue defect with a free flap. The standard techniques comprise the clinical examination, Doppler ultrasound and Doppler sonography for healthy patients without suspected direct trauma to the vascular system, and conventional digital subtraction angiography (DSA), respectively, in case of traumatized vessels or patients with peripheral arterial obstructive disease. Materials:We have conducted a prospective study for the comparison of the magnetic resonance angiography (MRA) to the conventional DSA. Fourteen patients were examined presurgically by means of both a conventional DSA and an MRA before undergoing planned microvascular coverage of tissue defects of the lower extremity. The surgeon, based on a questionnaire, assessed and compared both examination results according to their information content. Furthermore, the presurgically planned level and localization of the vascular anastomoses and the intraoperative findings were compared postoperatively. Results:The MRA examination yielded sufficient information on the vascular anatomy to enable the surgeon to carry out a detailed presurgical planning. Additionally, the use of MRA showed clear advantages with regard to both patient and user comfort. Conclusion:Taking into account the advantages for the assessment of vessels using MRA, in particular when considering the impact of the frequently varying vascular anatomy of the lower leg on reconstructive surgery, as well as the significantly lower morbidity rate of the examination itself, then the MRA must be regarded as a safe alternative to the DSA.
    European Journal of Trauma and Emergency Surgery 01/2007; 33(1):40-45. · 0.26 Impact Factor
  • Handchirurgie Mikrochirurgie Plastische Chirurgie - HANDCHIR MIKROCHIR PLAST CHIR. 01/2007; 39(5):345-349.
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    ABSTRACT: Liposuction is one of the most common aesthetic procedure used in plastic surgery. Reports are available on the results, the probable complications, and the feedback of patients. However, systematic studies dealing with these aspects using reliable large-enough data are still needed. The data comprised 116 procedures during a 6-year period up to 2005. The data were processed and categories of results were formed. Furthermore, a follow-up examination and a survey on the feedback of patients were carried out. Significant differences were identified in indications, results, and complications. The follow-up examinations and the survey showed satisfying results. In the majority of cases, surgeons were satisfied with the operations. In conclusion, if conducted by qualified surgeons in appropriate surgical conditions and postoperative care possibilities, liposuction may be considered as a reliable surgical procedure. The success of this procedure depends, however, on suitable infrastructure and operative competence.
    European Journal of Plastic Surgery 12/2006; 29(5):209-215.
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    ABSTRACT: Atrophies of the intrinsic muscles of the hand are considered to be a typical symptom of the "true neurologic" form of thoracic outlet syndrome (TOS). The classical form of this entity was described as early as 1970, consisting of a cervical rib or a prolonged transverse process of C7, complete with a fibrous band to the first thoracic rib, resulting in atrophy of the intrinsic muscles of the hand. All our TOS patients presenting with such atrophy displayed anatomical findings consistent with this definition. Based on this observation, the TOS classification currently in clinical use, which differentiates between "disputed" and "true neurologic" subgroups of the neurologic form, is reviewed. In all cases of "true neurologic TOS" with atrophy of the intrinsic muscles of the hand, the lateral thenar muscles are affected first. We present the electrophysiological long-term results of such thenar atrophies of seven patients with eight operated extremities after brachial plexus decompression. The amplitude of the neurographically measured potential over the opponens pollicis and the abductor pollicis brevis muscle, respectively, was defined as quantitative parameter for muscles atrophy. Neither distinct reinnervation nor progressive denervation was evident in any of the cases after a follow-up period, on average, of more than five years post surgery. These findings are in conflict with clinical observations reporting a major postoperative improvement of the motor deficits.
    Handchirurgie · Mikrochirurgie · Plastische Chirurgie 03/2006; 38(1):42-5. · 0.86 Impact Factor
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    ABSTRACT: Over the last few years, understanding of the pathophysiology of toxic epidermal necrolysis (TEN), or Lyell's disease, has substantially increased. However, differentiation of severe bullous skin disease remains a challenge for the clinician, and one that is often complicated by late patient referral. We performed a retrospective analysis of all patients with severe bullous skin disease, admitted between 1997 and 2002 to the Burn Centre, which is an integrated part of the Division for Plastic, Hand- and Reconstructive Surgery at the University Hospital of Zurich, Switzerland. We present an overview of our strategies and of the diagnostic and therapeutic difficulties encountered. The final diagnoses of the 18 patients referred to the unit were as follows: eight cases of TEN, one case of staphylococcal scalded-skin syndrome (SSSS), two cases of generalised drug eruption, one case of acute generalised exanthematic pustulosis and one case of febrile ulceronecrotic pityriasis lichenoides et varioliformis acuta (PLEVA). In two cases, the diagnosis remained unclear. In three cases, paraneoplastic origins were suspected but not demonstrated. The overall mortality rate was 33% (six of 18 patients). Remarkably, all patients with histologically confirmed TEN survived. Six of these patients were successfully treated with intravenous immunoglobulins (IVIG). The most common single causative drug inducing TEN (four cases out of eight) was Phenytoin. Establishing an accurate diagnosis-based on a skin biopsy, harvested at an early stage-is more important than ever, because more specific and effective therapeutic modalities are available. As these potentially life-threatening bullous skin disorders are rare, we recommend, that care be provided by an experienced interdisciplinary team, comprising a dermatologist, or dermatopathologist, an intensive care specialist and a plastic surgeon.
    British Journal of Plastic Surgery 02/2005; 58(1):73-80. · 1.29 Impact Factor